SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '53e135cbe643472f74378f8492913e3f98b128d93622fc08dcbc8b211f2c149e' 
  AND token = '+sHFvzz7jXg9lS1swbkCMYRCsZEUP4q3Jwh8W4lbaoI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}